Need help understanding the gestures

[shubham aggarwal]

Hello,

I came across this issue https://github.com/Polymer/polymer/issues/5674.

I am willing to contribute to it but I am new to the open-source world. The first step I did was to understand the gestures and how mouse events are working. I am not able to crack it down. Can anyone please help me to understand it and tell me how to proceed further?

Thanks!